You can take admission as private candidate where you don't have to attend classes.there are two ways one is to register yourself in nios(open schooling )through website or go you may visit your nearest AI (Study Centre)/Facilitation Centre and take help for on-line registration.registration fee for courses typically ranged from around 1,500 to 2,000, with additional costs for each subject and examination.

Second one is,you can choose distance education through a state open school. That will be equivalent to your state board.same process as nios.the fees ranges from 7k to 10 k including registration fees(it is for five subjects you need to pay more additional subject)

They arrange everything only you have to go for your exam you don't have give practical for 11 exam you can directly go school on your 12th practicals .